A new approach for creating double-stranded DNA biosensors

The principle of ‘sandwich’-type biosensors based on liquid-crystalline dispersions formed from [DNA-polycation] complexes is outlined. These biosensors will find application in the determination of a range of compounds and physical factors that affect the ability of a given polycationic molecule to maintain intermolecular crosslinks between neighbouring DNA molecules. In the case of liquid-crystalline dispersions formed from [DNA-protamine] complexes, the lowest concentration of hydrolytic enzyme (trypsin) detectable was ∼ 10 −14M.